Method for forming package structure with lid

ABSTRACT

A method for forming a package structure is provided, including forming an interconnect structure over a carrier substrate and forming a semiconductor die over a first side of the interconnect structure. A removable film is formed over the semiconductor die. The method includes forming a first stacked die package structure over the first side of the interconnect structure. A top surface of the removable film is higher than a top surface of the first stacked die package structure. The method includes forming a package layer, removing a portion of the package layer to expose a portion of the removable film, removing the removable film to form a recess, forming a lid structure over the semiconductor die and the first stacked die package structure. The lid structure has a main portion and a protruding portion disposed in the recess and extending from the main portion.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Divisional Application of U.S. patent applicationSer. No. 16/182,750, filed on Nov. 7, 2018, which claims priority toU.S. Provisional Application Ser. No. 62/732,010, filed on Sep. 17,2018, the entirety of which are incorporated by reference herein.

BACKGROUND

Semiconductor devices are used in a variety of electronic applications,such as personal computers, cell phones, digital cameras, and otherelectronic equipment. Semiconductor devices are typically fabricated bysequentially depositing insulating or dielectric layers, conductivelayers, and semiconductive layers of material over a semiconductorsubstrate, and patterning the various material layers using lithographyto form circuit components and elements thereon. Many integratedcircuits are typically manufactured on a single semiconductor wafer, andindividual dies on the wafer are singulated by sawing between theintegrated circuits along a scribe line. The individual dies aretypically packaged separately, in multi-chip modules, for example, or inother types of packaging.

New packaging technologies, such as package on package (PoP), have begunto be developed, in which a top package with a device die is bonded to abottom package, with another device die. By adopting the new packagingtechnologies, various packages with different or similar functions areintegrated together.

Although existing package structures and methods of fabricating packagestructure have generally been adequate for their intended purpose, theyhave not been entirely satisfactory in all respects.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It shouldbe noted that, in accordance with the standard practice in the industry,various features are not drawn to scale. In fact, the dimensions of thevarious features may be arbitrarily increased or reduced for clarity ofdiscussion.

FIGS. 1A-1I show cross-sectional representations of various stages offorming a package structure, in accordance with some embodiments of thedisclosure.

FIG. 2 shows a top-view representation of the package structure, inaccordance with some embodiments of the disclosure.

FIG. 3 shows a cross-sectional representation of a package structure, inaccordance with some embodiments of the disclosure.

FIGS. 4A-4G show cross-sectional representations of various stages offorming a package structure, in accordance with some embodiments of thedisclosure.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the subject matterprovided. Specific examples of components and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. For example, the formationof a first feature over or on a second feature in the description thatfollows may include embodiments in which the first and second featuresare formed in direct contact, and may also include embodiments in whichadditional features may be formed between the first and second features,such that the first and second features may not be in direct contact. Inaddition, the present disclosure may repeat reference numerals and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various embodiments and/or configurations discussed.

Some variations of the embodiments are described. Throughout the variousviews and illustrative embodiments, like reference numbers are used todesignate like elements. It should be understood that additionaloperations can be provided before, during, and after the method, andsome of the operations described can be replaced or eliminated for otherembodiments of the method.

Other features and processes may also be included. For example, testingstructures may be included to aid in the verification testing of the 3Dpackaging or 3DIC devices. The testing structures may include, forexample, test pads formed in a redistribution layer or on a substratethat allows the testing of the 3D packaging or 3DIC, the use of probesand/or probe cards, and the like. The verification testing may beperformed on intermediate structures as well as the final structure.Additionally, the structures and methods disclosed herein may be used inconjunction with testing methodologies that incorporate intermediateverification of known good dies to increase the yield and decreasecosts.

Embodiments for a semiconductor device structure and method for formingthe same are provided. FIGS. 1A-1I show cross-sectional representationsof various stages of forming a package structure 100 a, in accordancewith some embodiments of the disclosure. The package structure may be achip-on-wafer-on-substrate (CoWoS) package or another suitable package.A semiconductor die and a memory stacked die structure are formed overan interconnect structure, and a T-shaped lid structure is formed overthe semiconductor die and the memory stacked die structure. The packagestructure is a fan-out package structure. The term of “fan-out” meansthat the I/O pads on a die can be redistributed to a greater area thanthe die itself, and hence the number of I/O pads packed on the surfacesof the dies can be increased.

Referring to FIG. 1A, a carrier substrate 102 is provided. The carriersubstrate 102 is configured to provide temporary mechanical andstructural support during subsequent processing steps, in accordancewith some embodiments. The carrier substrate 102 includes glass, siliconoxide, aluminum oxide, metal, a combination thereof, and/or the like, inaccordance with some embodiments. The carrier substrate 102 includes ametal frame, in accordance with some embodiments.

An interconnect structure 110 is formed over the carrier substrate 102.The interconnect structure 110 may be used as a redistribution (RDL)structure for routing. The interconnect structure 110 includes multipledielectric layers 104 and multiple conductive layers 106. In someembodiments, some of the conductive layers 106 are exposed at orprotruding from the top surface of the top of the dielectric layers 104.The exposed or protruding conductive layers 106 may serve as bondingpads where conductive bumps (such as tin-containing solder bumps) and/orconductive pillars (such as copper pillars) will be formed later.

The dielectric layers 104 may be made of or include one or more polymermaterials. The polymer material(s) may include polybenzoxazole (PBO),polyimide (PI), one or more other suitable polymer materials, or acombination thereof. In some embodiments, the polymer material isphotosensitive. In some embodiments, some or all of the dielectriclayers 104 are made of or include dielectric materials other thanpolymer materials. The dielectric material may include silicon oxide,silicon carbide, silicon nitride, silicon oxynitride, one or more othersuitable materials, or a combination thereof.

Afterwards, as shown in FIG. 1B, a semiconductor die 120, a firststacked die package structure 130 a and a second stacked die packagestructure 130 b are formed over the carrier substrate 102, in accordancewith some embodiments of the disclosure. The semiconductor die 120 isbetween the first stacked die package structure 130 a and the secondstacked die package structure 130 b.

In some embodiments, a semiconductor die 120 is disposed over thecarrier substrate 102. The semiconductor die 120 is sawed from a wafer,and may be a “known-good-die”. The semiconductor die 120 may be asystem-on-chip (SoC) chip. In some other embodiments, the semiconductordie 120 is a system on integrated circuit (SoIC) device that includestwo or more chips with integrated function. The semiconductor die 120 isdisposed over the interconnection structure 110. The semiconductor die120 has a substrate 122, and a removable film 123 is formed over thesubstrate 122. The top surface of the removable film 123 is higher thanthe top surface of the first stacked die package structure 130 a and thetop surface of the second stacked die package structure 130 b.

In some embodiments, the substrate 122 is silicon (Si) substrate. Theremovable film 123 is used as a release film and will be removed in thefollowing process. In some embodiments, the removable film 123 is madeof grindable and low out-gassing materials. In some embodiments, theremovable film 123 is made of thermoplastic material, such aspolyethylene (PE), polypropylene (PP), polyethyleneterephthalate (PET)or another applicable material.

In some embodiments, a number of conductive pads 124 are formed belowthe semiconductor die 120, and each of the conductive pads 124 is bondedto the conductive layer 106 of the interconnect structure 110 through aconductive connector 126. The conductive pads 124 are made of metalmaterials, such as copper (Cu), copper alloy, aluminum (Al), aluminumalloy, tungsten (W), tungsten alloy, titanium (Ti), titanium alloy,tantalum (Ta) or tantalum alloy. In some embodiments, the conductive pad124 is formed by an electroplating, electroless plating, printing,chemical vapor deposition (CVD) process or physical vapor deposition(PVD) process. The conductive connector 126 is made of solder materials,such as tin (Sn), SnAg, SnPb, SnAgCu, SnAgZn, SnZn, SnBiIn, SnIn, SnAu,SnPb, SnCu, SnZnIn, SnAgSb or another applicable material. In someembodiments, the conductive connector 126 is formed by electroplating,electroless plating, printing, chemical vapor deposition (CVD) processor physical vapor deposition (PVD) process.

The first stacked die package structure 130 a and the second stacked diepackage structure 130 b are disposed over the interconnect structure110. The first stacked die package structure 130 a and the secondstacked die package structure 130 b are at opposite sides of thesemiconductor die 120. Each of the first stacked die package structure130 a and the second stacked die package structure 130 b includes anumber of semiconductor dies 132A, 132B, 132C, 132D. In someembodiments, the semiconductor dies 132A, 132B, 132C, 132D are memorydies. The semiconductor die 120 has a different function from each ofthe plurality of the memory dies. The memory dies may include staticrandom access memory (SRAM) devices, dynamic random access memory (DRAM)devices, high bandwidth memory (HBM) or another memory dies. The numberof the semiconductor dies 132A, 132B, 132C, 132D are not limited tofour, and the number can be adjusted according to the actualapplication.

The semiconductor dies 132A, 132B, 132C, 132D are stacked on a bufferdie (or base die) 131 that performs as a logic circuit. Thesemiconductor dies 132A, 132B, 132C, 132D are bonded to each other by anumber of bonding structures 136. A number of through substrate vias(TSVs) 134 are formed in the semiconductor dies 132A, 132B, 132C, 132D.The signal between the semiconductor dies 132A, 132B, 132C, 132D may betransferred through the through substrate vias (TSVs) 134 and thebonding structures 136.

An underfill layer 138 is formed between the semiconductor dies 132A,132B, 132C, 132D to protect the bonding structures 136. In someembodiments, the underfill layer 138 includes an epoxy-based resin withfillers dispersed therein. The fillers may include insulating fibers,insulating particles, other suitable elements, or a combination thereof.A molding compound 140 protects the semiconductor dies 132A, 132B, 132C,132D. In some embodiments, the molding compound 140 may include anepoxy-based resin with fillers dispersed therein. The fillers mayinclude insulating fibers, insulating particles, other suitableelements, or a combination thereof. In some embodiments, the size and/ordensity of the fillers dispersed in the underfill layer 138 is smallerthan those dispersed in the molding compound 140.

In some embodiments, a number of conductive pads 144 are formed on thefirst stacked die package structure 130 a and the second stacked diepackage structure 130 b, and each of the conductive pads 144 is bondedto the conductive layer 106 of the interconnect structure 110 through aconductive connector 146.

The conductive pads 144 are made of metal materials, such as copper(Cu), copper alloy, aluminum (Al), aluminum alloy, tungsten (W),tungsten alloy, titanium (Ti), titanium alloy, tantalum (Ta) or tantalumalloy. In some embodiments, the conductive pad 144 is formed by anelectroplating, electroless plating, printing, chemical vapor deposition(CVD) process or physical vapor deposition (PVD) process.

The conductive connector 146 is made of solder materials, such as tin(Sn), SnAg, SnPb, SnAgCu, SnAgZn, SnZn, SnBiIn, SnIn, SnAu, SnPb, SnCu,SnZnIn, SnAgSb or another applicable material. In some embodiments, theconductive connector 146 is formed by electroplating, electrolessplating, printing, chemical vapor deposition (CVD) process or physicalvapor deposition (PVD) process.

The semiconductor die 120 has a first height H₁ along a verticaldirection, and the first stacked die package structure 130 a has asecond height H₂ along the vertical direction. The second height H₂ isgreater than the first height H₁. In some embodiments, the first heightH₁ of the semiconductor die 120 is in a range from about 750 μm to about850 μm. In some embodiments, the second height H₂ of the first stackeddie package structure 130 a in a range from about 900 μm to about 1000μm. In some embodiments, a height difference (ΔH=H₂−H₁) between thesecond height and the first height H₁ is in a range from about 50 μm toabout 150 μm. When the height difference is within above-mentionedrange, the package structure 100 a have a good heat dissipationefficiency.

Furthermore, since the first stacked die package structure 130 aincludes multiple semiconductor dies 132A, 132B, 132C, 132D, the heightof each of the semiconductor dies 132A, 132B, 132C, 132D is smaller thanthe first height H₁ of the semiconductor die 120.

Afterwards, as shown in FIG. 1C, an underfill layer 148 is formedbetween the semiconductor die 120, the first stacked die packagestructure 130 a, the second stacked die package structure 130 b, and theinterconnect structure 110, in accordance with some embodiments of thedisclosure. The underfill layer 148 surrounds and protects theconductive connectors 126 and 146. In some embodiments, the underfilllayer 148 is in direct contact with the conductive connectors 126 and146.

In some embodiments, the underfill layer 148 is made of or includes apolymer material. The underfill layer 148 may include an epoxy-basedresin. In some embodiments, the underfill layer 148 includes fillersdispersed in the epoxy-based resin.

In some embodiments, the formation of the underfill layer 148 involvesan injecting process, a spin-on process, a dispensing process, a filmlamination process, an application process, one or more other applicableprocesses, or a combination thereof. In some embodiments, a thermalcuring process is used during the formation of the underfill layer 148.

Afterwards, a package layer 150 is formed over the underfill layer 148.The package layer 150 is also formed over the removable film 123. Thereis an interface between the underfill layer 148 and the package layer150, and the interface is lower than the top surface of thesemiconductor die 120.

The package layer 150 surrounds and protects the semiconductor die 120,the first stacked die package structure 130 a and the second stacked diepackage structure 130 b. In some embodiments, the package layer 150 isin direct contact with a portion of the semiconductor die 120, a portionof the first stacked die package structure 130 a and a portion of thesecond stacked die package structure 130 b.

The package layer 150 is made of a molding compound material. Themolding compound material may include a polymer material, such as anepoxy-based resin with fillers dispersed therein. In some embodiments, aliquid molding compound material is applied over the semiconductor die120, the first stacked die package structure 130 a and the secondstacked die package structure 130 b. The liquid molding compoundmaterial may flow into a space between the semiconductor die 120, thefirst stacked die package structure 130 a and the second stacked diepackage structure 130 b. A thermal process is then used to cure theliquid molding compound material and to transform it into the packagelayer 150.

Afterwards, as shown in FIG. 1D, a portion of the removable film 123 isremoved to expose the top surface of the removable film 123, inaccordance with some embodiments of the disclosure. In some embodiments,the portion of the removable film 123 is removed by a planarizationprocess, such as a chemical mechanical polishing (CMP) process. Inaddition, since the first stacked die package structure 130 a and thesecond stacked die package structure 130 b are protected by the packagelayer 150, the top surface of the first stacked die package structure130 a and the top surface of the second stacked die package structure130 b are not exposed by the CMP process.

Afterwards, as shown in FIG. 1E, a frame tape 160 is formed over theremovable film 123 and the package layer 150, in accordance with someembodiments of the disclosure. Afterwards, the carrier substrate 102 isremoved.

The frame tape 160 is used as a temporary substrate. The frame tape 160substrate provides mechanical and structural support during subsequentprocessing steps, such as those described in more detail later. In someembodiments, the removable film 123 and the first stacked die packagestructure 130 a are adhered to the frame tape 160. For example, theremovable film 123 and the package layer 150 are attached to the frametape 160 through an adhesive layer (not shown). The adhesive layer isused as a temporary adhesive layer.

Next, as shown in FIG. 1F, a portion of the interconnect structure 110is removed, in accordance with some embodiments of the disclosure. As aresult, the conductive layer 106 of the interconnect structure 110 isexposed.

Afterwards, a number of the conductive connectors 164 are formed overthe exposed conductive layer 106 of the interconnect structure 110. Theconductive connectors 164 are electrically connected to the conductivelayer 106 of the interconnect structure 110. In some embodiments, theconductive connectors 164 are referred to as controlled collapse chipconnection (C4) bumps. In some other embodiments, the conductiveconnectors 164 is micro bumps, electroless nickel-electrolesspalladium-immersion gold technique (ENEPIG) formed bumps, ball gridarray (BGA) bumps, or the like.

It should be noted that the conductive connectors 126 are formed on thetop surface of the interconnect structure 110, and the conductiveconnectors 164 are formed on the bottom surface of the interconnectstructure 110. There is a first gap between two adjacent conductiveconnectors 126, and a second gap between two adjacent conductiveconnectors 164. The second gap is greater than the first gap.Accordingly, the interconnect structure 110 enables the fan-outconnection.

Subsequently, a singulation process is performed to separate thewafer-level package structure 100 a into multiple die-level packagestructure 100 a. In some embodiments, the singulation process is adicing process.

Next, as shown in FIG. 1G, the frame tape 160 is removed, and then theremovable film 123 is removed, in accordance with some embodiments ofthe disclosure. As a result, a recess 125 is formed over the top surfaceof the semiconductor die 120. The entirety top surface of thesemiconductor die 120 is exposed. The package layer 150 is exposed bythe sidewall surface of the recess 125. In some embodiments, theremovable film 123 is removed by an etching process. For example, theremovable film 123 is removed by a wet etching process, such as an acidsolution.

Subsequently, as shown in FIG. 1H, an adhesive layer 170 is formed overthe semiconductor die 120 and the package layer 150, in accordance withsome embodiments of the disclosure.

The adhesive layer 170 is conformally formed in the recess 125, and overthe semiconductor die 120 and the package layer 150. Therefore, theadhesive layer 170 includes a top portion directly over the firststacked die package structure 130 a and the second stacked die packagestructure 130 b and a bottom portion directly over the semiconductor die120. The sidewall surface of the bottom portion of the adhesive layer170 is substantially aligned with the sidewall surface of thesemiconductor die 120. In addition, the bottom portion of the adhesivelayer 170 is lower than the top surface of the first stacked die packagestructure 130 a. In other words, the bottommost surface of the adhesivelayer 170 is lower than the top surface of the first stacked die packagestructure 130 a.

The adhesive layer 170 is made of polymer having a good thermalconductivity. In some embodiments, the adhesive layer 170 includesthermal interface material (TIM).

Next, a lid structure 172 is formed over the adhesive layer 170.Accordingly, the heat generated from the semiconductor die 120, thefirst stacked die package structure 130 a and the second stacked diepackage structure 130 b may dissipate to the lid structure 172, and thendissipate to the external environment. In some embodiments, a bottommostsurface of the lid structure 172 is lower than the top surface of thefirst stacked die package structure 130 a.

The lid structure 172 has a main portion 172 a and a protruding portion172 b extending from the main portion 172 a. In some embodiments, thelid structure 172 has a T-shaped structure. The dashed line shown inFIG. 1H is used to define the profile of the main portion 172 a and theprotruding portion 172 b of the lid structure 172. There is no realinterface between the main portion 172 a and the protruding portion 172b. The main portion 172 a has a rectangular shape, and the protrudingportion 172 b also has a rectangular shape. The size of the main portion172 a is greater than that of the protruding portion 172 b.

Since the recess 125 is not completely filled with the adhesive layer170, the remaining recess 125 is filled with the lid structure 172. Theprotruding portion 172 b of the lid structure 172 is directly over thesemiconductor die 120.

The protruding portion 172 b of the lid structure 172 has a bottomsurface, the bottom surface of the protruding portion 172 b is higherthan a top surface of the semiconductor die 120 and lower than the topsurface of the first stacked die package structure 130 a and the topsurface of the second stacked die package structure 130 b.

The lid structure has a top surface with a top width W₁ and a bottomsurface with a bottom width W₂. The top width Wi is greater than thebottom width W₂. The protruding portion 172 b has a protruding heightP₁. In some embodiments, the protruding height P₁ is in a range fromabout 50 μm to about 150 μm.

Afterwards, as shown in FIG. 1I, the package structure 100 a is bondedto a package substrate 180 through the conductive connectors 164, inaccordance with some embodiments. In some embodiments, the packagesubstrate 180 is a printed circuit board (PCB), a ceramic substrate oranother suitable package substrate. The interconnect structure 110 isused as fan out electrical connection to connect the signals of thesemiconductor die 120, the first stacked die package structure 130 a andthe second stacked die package structure 130 b to the package substrate180.

In the first embodiment, the first stacked die package structure 130 aand the second stacked die package structure 130 b are covered by thepackage layer 150 and not removed during removing a portion of theremovable film 123. The semiconductor dies 132A, 132B, 132C and 132D inthe first stacked die package structure 130 a and the second stacked diepackage structure 130 b are not damaged during the planarizationprocess. The semiconductor dies 132A, 132B, 132C and 132D respectivelyhave different functions, and they are not damaged to maintain theirfunction. Therefore, the quality and reliability of the first stackeddie package structure 130 a and the second stacked die package structure130 b are improved.

As the requirement for the memory capacity of the first stacked diepackage structure 130 a is gradually increased, the number of thesemiconductor dies 132A, 132B, 132C, 132D is increased. Accordingly, thefirst stacked die package structure 130 a is higher than thesemiconductor die 120, and a gap is between the semiconductor die 120and the first stacked die package structure 130 a. In order to providehigh heat dissipation, the lid structure 172 is designed to have aprotruding portion to insert into the gap between the semiconductor die120 and the first stacked die package structure 130 a.

In some other embodiments, if a planar lid structure is disposed overthe semiconductor die 120 and the first stacked die package structure130 a, the adhesive layer 170 will be thick to compensate the heightdifference between the semiconductor die 120 and the first stacked diepackage structure 130 a. However, the heat transfer coefficient (k) ofthe adhesive layer 170 is relatively smaller than that of the lidstructure 172. The thick adhesive layer 170 directly over thesemiconductor die 120 will degrade the heat dissipation. The lidstructure 172 having the protruding portion 172 b, rather than thickadhesive layer 170, is used to fill the height difference generated fromthe semiconductor die 120 and the first stacked die package structure130 a. The lid structure 172 provides high heat dissipation efficiency,and therefore, the performance of the of the package structure 100 a isimproved.

In addition, the semiconductor die 120 and the first stacked die packagestructure 130 a are directly formed on the interconnect structure 110(or called as redistribution layer (RDL)), and they are electricallyconnected to the package substrate 180 through the interconnectstructure without using additional interposer structure. Therefore, thefan-out package structure 100 a is obtained and the fabrication time andcost are reduced.

FIG. 2 shows a top-view representation of the package structure 100 a,in accordance with some embodiments of the disclosure. FIG. 1C showcross-sectional representation taken along line A-A′ of FIG. 2.

As shown in FIG. 2, the semiconductor die 120 is located at the center,and four stacked die package structure 130 a, 130 b are disposed atopposite sides of the semiconductor die 120. Two first stacked diepackage structures 130 a are symmetric to two second stacked die packagestructures 130 b with respect to the semiconductor die 120. The area ofthe semiconductor die 120 is greater than the area of each of the firststacked die package structures 130 a. In some embodiments, a ratio ofthe area of the first stacked die package structures 130 a to the areaof the semiconductor die 120 is in a range from about 30% to about 60%.

FIG. 3 shows a cross-sectional representation of a package structure 100b, in accordance with some embodiments of the disclosure. The packagestructure 100 b is similar to, or the same as, the package structure 100a shown in FIG. 1I, except that the first stacked die package structure130 a and the second stacked die package structure 130 b have differentheights. Processes and materials used to form the semiconductor packagestructure 100 b may be similar to, or the same as, those used to formthe semiconductor device structure 100 a and are not repeated herein.

The semiconductor die 120 has the first height H₁, the first stacked diepackage structure 130 a has the second height H₂, and the second stackeddie package structure 130 b has the third height H₃. The third height H₃is greater than the second height H₂, and the second height H₂ isgreater than the first height H₁.

FIGS. 4A-4G show cross-sectional representations of various stages offorming a package structure 100 c, in accordance with some embodimentsof the disclosure. The package structure 100 c is similar to, or thesame as, the package structure 100 a shown in FIG. 1I, except that thetop surface of the first stacked die package structure 130 a and the topsurface of the second stacked die package structure 130 b are in directcontact with the adhesive layer 170.

As shown in FIG. 4A, the interconnect structure 110 is formed over thecarrier substrate 102, and the first stacked die package structure 130 aand the second stacked die package structure 130 b are disposed over theinterconnect structure 110. Each of the first stacked die packagestructure 130 a and the second stacked die package structure 130 bincludes a number of semiconductor dies 132A, 132B, 132C, 132D stackedon a buffer die (or base die) 131 that performs as a logic circuit.

The underfill layer 148 is formed between the semiconductor die 120, thefirst stacked die package structure 130 a, the second stacked diepackage structure 130 b, and the interconnect structure 110. Next, thepackage layer 150 is formed over the underfill layer 148.

Next, as shown in FIG. 4B, a portion of the removable film 123, aportion of the first stacked die package structure 130 a and a portionof the second stacked die package structure 130 b are removed, inaccordance with some embodiments of the disclosure. As a result, the topsurface of the first stacked die package structure 130 a and the topsurface of the second stacked die package structure 130 b are exposed.In some embodiments, the no-functional region is removed, and thus thefunction of the semiconductor dies 132A, 132B, 132C and 132D aremaintained.

Afterwards, as shown in FIG. 4C, the removable film 123, the exposed topsurface of the first stacked die package structure 130 a and the exposedtop surface of the second stacked die package structure 130 b areattached to the frame tape 160, in accordance with some embodiments ofthe disclosure. Afterwards, the carrier substrate 102 is removed.

Subsequently, as shown in FIG. 4D, a portion of the interconnectstructure 110 is removed to expose the conductive layer 106, inaccordance with some embodiments of the disclosure. Next, a number ofthe conductive connectors 164 are formed over the exposed conductivelayer 106 of the interconnect structure 110. The conductive connectors164 are electrically connected to the conductive layer 106 of theinterconnect structure 110. In some embodiments, the conductiveconnectors 164 are referred to as controlled collapse chip connection(C4) bumps. Subsequently, a singulation process is performed to separatethe wafer-level package structure 100 a into multiple die-level packagestructure 100 a. In some embodiments, the singulation process is adicing process.

Afterwards, as shown in FIG. 4E, the frame tape 160 is removed, and thenthe removable film 123 is removed, in accordance with some embodimentsof the disclosure. As a result, the recess 125 is formed over the topsurface of the semiconductor die 120.

Next, as shown in FIG. 4F, the adhesive layer 170 is formed over thesemiconductor die 120 and the package layer 150, in accordance with someembodiments of the disclosure. Afterwards, the lid structure 172 isformed over the adhesive layer 170. The lid structure 172 has theprotruding portion 172 d directly over the semiconductor die 120 toeffectively dissipate the heat.

Afterwards, as shown in FIG. 4G, the package structure 100 c is bondedto a package substrate 180 through the conductive connectors 164, inaccordance with some embodiments. In some embodiments, the packagesubstrate 180 is a printed circuit board (PCB).

The difference between FIG. 4G and FIG. 1I is that no package layer 150is between the top surface of the first stacked die package structure130 a and the adhesive layer 170 in FIG. 4G, and the first stacked diepackage structure 130 a is in direct contact with the adhesive layer170. As a result, the heat generated from the first stacked die packagestructure 130 a and the semiconductor die 120 can be directly transferthrough the adhesive layer 170 to the lid structure 172. Therefore, theheat dissipation efficiency is improved. The package structure 100 c canbe applied to a high power device due to the advantage of highdissipation efficiency.

Embodiments for forming a package structure and method for formation thesame are provided. The package structure includes an interconnectstructure, and a semiconductor die and a stacked die package structureformed over the interconnect structure. The stacked die packagestructure includes multiple semiconductor dies. The height of thestacked die package structure is higher than that of the semiconductordie. In order to compensate the height difference, a removable film istemporarily formed directly over the semiconductor die, and then isremoved to form a recess. In order to maintain the high heatdissipation, a lid structure with a protruding portion corresponding tothe recess is designed. Therefore, the heat is efficiently dissipated bythe lid structure and the performance of the package structure isimproved.

A method for forming a package structure is provided in someembodiments. The method includes forming an interconnect structure overa carrier substrate, forming a semiconductor die over a first side ofthe interconnect structure, wherein a removable film is formed over thesemiconductor die, forming a first stacked die package structure overthe first side of the interconnect structure, wherein a top surface ofthe removable film is higher than a top surface of the first stacked diepackage structure, forming a package layer over the semiconductor dieand the first stacked die package structure, removing a portion of thepackage layer to expose a portion of the removable film, removing theremovable film to form a recess over the semiconductor die, and forminga lid structure over the semiconductor die and the first stacked diepackage structure, wherein the lid structure has a main portion and aprotruding portion extending from the main portion, and the protrudingportion is disposed in the recess.

A method for forming a package structure is provided in someembodiments. The method includes forming a semiconductor die over afirst side of an interconnect structure, wherein the semiconductor diehas a first height, forming a first stacked die package structure overthe first side of the interconnect structure, wherein the first stackeddie package structure has a second height, and the second height isgreater than the first height, forming a package layer between thesemiconductor die and the first stacked die package structure, whereinthe package layer is in contact with sidewalls of the semiconductor die,and forming a lid structure over the semiconductor die and the firststacked die package structure, wherein the lid comprises a main portionand a protruding portion extending from the main portion, and theprotruding portion is directly over the semiconductor die.

A method for forming a package structure is provided in someembodiments. The method includes forming a semiconductor die over afirst side of an interconnect structure, forming a first stacked diepackage structure over the first side of the interconnect structure,forming an underfill layer between the semiconductor die and the firststacked die package structure, and forming a package layer over theunderfill layer, wherein an interface is between the underfill layer andthe package layer, and the interface is lower than a top surface of thesemiconductor die.

The foregoing outlines features of several embodiments so that thoseskilled in the art may better understand the aspects of the presentdisclosure. Those skilled in the art should appreciate that they mayreadily use the present disclosure as a basis for designing or modifyingother processes and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein.Those skilled in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure, and that they may make various changes, substitutions, andalterations herein without departing from the spirit and scope of thepresent disclosure.

What is claimed is:
 1. A method for forming a package structure,comprising: forming an interconnect structure over a carrier substrate;forming a semiconductor die over a first side of the interconnectstructure, wherein a removable film is formed over the semiconductordie; forming a first stacked die package structure over the first sideof the interconnect structure, wherein a top surface of the removablefilm is higher than a top surface of the first stacked die packagestructure; forming a package layer over the semiconductor die and thefirst stacked die package structure; removing a portion of the packagelayer to expose a portion of the removable film; removing the removablefilm to form a recess over the semiconductor die; and forming a lidstructure over the semiconductor die and the first stacked die packagestructure, wherein the lid structure has a main portion and a protrudingportion extending from the main portion, and the protruding portion isdisposed in the recess.
 2. The method for forming the package structureas claimed in claim 1, further comprising: removing a portion of thefirst stacked die package structure during removing the portion of thepackage layer, such that a portion of the first stacked die packagestructure is exposed.
 3. The method for forming the package structure asclaimed in claim 1, further comprising: adhering the removable film andthe first stacked die package structure to a frame tape; and removingthe carrier substrate.
 4. The method for forming the package structureas claimed in claim 3, further comprising: removing a portion of theinterconnect structure, wherein the interconnect structure comprises aplurality of conductive layers in a plurality of dielectric layers, anda portion of the conductive layers is exposed after removing the portionof the interconnect structure.
 5. The method for forming the packagestructure as claimed in claim 1, further comprising: forming an adhesivelayer over the semiconductor die and the first stacked die packagestructure, wherein a portion of the adhesive layer is lower than the topsurface of the first stacked die package structure.
 6. A method forforming a package structure, comprising: forming a semiconductor dieover a first side of an interconnect structure, wherein thesemiconductor die has a first height; forming a first stacked diepackage structure over the first side of the interconnect structure,wherein the first stacked die package structure has a second height, andthe second height is greater than the first height; forming a packagelayer between the semiconductor die and the first stacked die packagestructure, wherein the package layer is in contact with sidewalls of thesemiconductor die; and forming a lid structure over the semiconductordie and the first stacked die package structure, wherein the lidcomprises a main portion and a protruding portion extending from themain portion, and the protruding portion is directly over thesemiconductor die.
 7. The method for forming the package structure asclaimed in claim 6, further comprising: forming an underfill layer belowthe first stacked die package structure, wherein the underfill layercovers the sidewalls of the semiconductor die.
 8. The method for formingthe package structure as claimed in claim 7, wherein the underfill layercontinuously extends below the semiconductor die and the first stackeddie package structure.
 9. The method for forming the package structureas claimed in claim 7, wherein the package layer is separated from thefirst stacked die package structure by the underfill layer.
 10. Themethod for forming the package structure as claimed in claim 6, furthercomprising forming an adhesive layer, wherein the adhesive layercontinuously extends between the semiconductor die and the lidstructure, and between the first stacked die package structure and thelid structure.
 11. The method for forming the package structure asclaimed in claim 10, wherein the first stacked die package structure isseparated from the adhesive layer.
 12. The method for forming thepackage structure as claimed in claim 10, wherein the first stacked diepackage structure is in contact with the adhesive layer.
 13. The methodfor forming the package structure as claimed in claim 12, wherein theadhesive layer is in contact with a top surface and a side surface ofthe package layer, and the top surface and the side surface of thepackage layer face different directions.
 14. The method for forming thepackage structure as claimed in claim 10, wherein a distance between thesemiconductor die and a first bottom surface of the protruding portionfacing the semiconductor die is less than a distance between the firststacked die package structure and a second bottom surface of the lidstructure facing the first stacked die package structure.
 15. The methodfor forming the package structure as claimed in claim 6, wherein thesemiconductor die is wider than the protruding portion.
 16. A method forforming a package structure, comprising: forming a semiconductor dieover a first side of an interconnect structure; forming a first stackeddie package structure over the first side of the interconnect structure;forming an underfill layer between the semiconductor die and the firststacked die package structure; and forming a package layer over theunderfill layer, wherein an interface is between the underfill layer andthe package layer, and the interface is lower than a top surface of thesemiconductor die.
 17. The method for forming the package structure asclaimed in claim 16, further comprising forming a lid structure over thesemiconductor die and the first stacked die package structure, whereinthe lid structure has a T-shaped structure.
 18. The method for formingthe package structure as claimed in claim 16, further comprising forminga second stacked die package structure over the first side of theinterconnect structure, wherein the semiconductor die is between thefirst stacked die package structure and the second stacked die packagestructure.
 19. The method for forming the package structure as claimedin claim 15, wherein the package layer is in contact with a top surfaceof the first stacked die package structure, and is separated from a sidesurface of the first stacked die package structure by the underfilllayer.
 20. The method for forming the package structure as claimed inclaim 15, wherein an angle between the interface and a side surface ofthe semiconductor die is an acute angle.